Truncated domes (AKA detectable warnings, tactile paving, detectable warning surfaces) are ground surface indicators designed to assist and warn pedestrians who are blind or visually impaired.
Truncated domes feature a unique pattern of cones that are detected by a cane or underfoot which are used to alert people with visual impairments of their approach to streets and hazardous drop-offs.
Truncated domes were first implemented by Japan in the mid 1960’s and were later expanded to include United Kingdom and Australia. The United States did not pick up on the standard until the early 1990’s, with Canada soon after that.
As of the beginning of 2014, more than 18 countries have adopted the practice of installing truncated domes in front of rail lines, schools, city crosswalks, government buildings, etc.